Yes, people can demonstrably do this with high reliability.

Some humans carry detailed models of CPU microarchitectures in their heads, against which they can design code from first principles that will be nearly ideal on the first try. It is repeatable and verifiable. The best people can accurately predict the measured performance before writing a line of code.

Measurement is useful in cases where the model of software and hardware interaction is materially incomplete. In most cases this is because the people writing the software have insufficient understanding of the hardware. Having a limited understanding of the hardware is a choice.

It would be surprising if this wasn't possible.